---
status: located
opened: 2026-10-03
located-in:
  - mesh-controller
fixed-by:
amended-design:
---

# 211 — A bundle is built in the same tier as the toolchain it is compiled in, against the old toolchain

## What was observed

2026-10-03, merging a runtime change that needed a new SDK release. The SDK was published first;
then the merge of the tools repository planned two tiers, and the first held both the toolchain
images and the runtime's own bundle:

```
> tier 0
    mesh-tools             asked
    node-tools             built from 8e30ea9f
```

The bundle was built while its toolchain image was still being built. A TypeScript bundle's
dependencies are copied from the toolchain image it is compiled in
([design 38](../../03-DESIGN/01-to-be/38-building-the-operators-machine.md) WP3), so this one was
compiled and packed against the toolchain as it stood before the merge — carrying the old SDK —
and was recorded as built from the new commit.

## Why it matters beyond this instance

Every bundle compiled by a toolchain depends on the module that publishes that toolchain, and the
planner does not know it: a manifest names its toolchain by `language`, not in `build.on`, so the
dependency is implicit and the tiers are computed without it. Whenever a change touches the
toolchain and a bundle in one merge — or the toolchain's own repository holds a bundle, as this one
does — the bundle is built against the previous toolchain and reported current. Nothing fails; the
bundle simply carries yesterday's dependencies under today's commit.

## Diagnosis

Owner mesh-controller: the planner orders a merge's modules by `build.on`; the builder's toolchain
for a bundle (`ToolchainFor(language)`: the module and artifact it is compiled in) is not part of
that order. **Fix direction:** the planner treats a bundle's toolchain as a `build.on` it did not
have to write — a bundle of language L depends on the module that publishes L's toolchain — so the
bundle lands in the tier after it. A test: a merge touching the toolchain module and a TypeScript
bundle plans the bundle one tier later. Worked around on the day by building the bundle again once
the toolchain was built.